How can I loop through screen areas and point to specific area?
Not sure what do you mean the second one but you can select the second one with further conditional list:
[area for area in bpy.context.screen.areas if area.type == 'IMAGE_EDITOR'][1]

And also there are properties x and y for area type, which indicate the bottom-left corner position in your screen. You can write some sorting function to select the desired one.
Area(bpy_struct) — Blender Python API